Park Jin Hyun, Yoo Seok Yeol, Shin Myoung Hyeon, Jeong Sungwook, Park Yoonsu, Bae Han Yong
Department of Chemistry, Sungkyunkwan University, Suwon, Republic of Korea.
Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea.
Nat Commun. 2025 Jul 2;16(1):6090. doi: 10.1038/s41467-025-61265-4.
Asymmetric binary catalysis, particularly combining chiral Brønsted acids with Lewis acids, is an emerging strategy in synthetic chemistry. Although a few catalyst combinations exist for stereoselective transformations, their scope is generally limited to pre-organized, activated substrates. Here, we report binary catalysis combining an organosuperacid with bismuth, where the counteranion of chiral N-triflyl phosphoramide acts as a flexible-coordinating ligand. This system demonstrates exceptional reactivity and enantioselectivity in the asymmetric allylation of α-keto thioesters, forming enantio-enriched α-hydroxy thioesters with a tetra-substituted stereogenic carbon center (up to > 99% yield and 97% ee). The success is attributed to bismuth's flexibility during activation, enhancing also interactions with the thioester-tethered substrate. Integrated experimental, analytical, and computational studies highlight the unique assembly enabled by the chiral Brønsted acid and bismuth salt system.
不对称二元催化，特别是将手性布朗斯特酸与路易斯酸相结合，是合成化学中一种新兴的策略。尽管存在一些用于立体选择性转化的催化剂组合，但其范围通常限于预先构建的、活化的底物。在此，我们报道了一种将有机超强酸与铋相结合的二元催化，其中手性N-三氟甲磺酰基磷酰胺的抗衡阴离子作为柔性配位配体。该体系在α-酮硫酯的不对称烯丙基化反应中表现出卓越的反应活性和对映选择性，形成具有四取代立体中心的对映体富集的α-羟基硫酯（产率高达>99%，对映体过量值高达97%）。成功的原因在于铋在活化过程中的灵活性，这也增强了其与硫酯连接底物的相互作用。综合实验、分析和计算研究突出了手性布朗斯特酸和铋盐体系实现的独特组装。
